Atomic number of Mg is 12, give the number of electrons it `Mg^(2+)` ion.

The atomic number of the inert gas in which the total number of d-electrons is equal to the difference in the numbers of total p-and s-electrons is-

(i) The electronic configuration of an atom is [Z](n-2) f^(14)(n-1)d^(1)ns^(2) . What is the minimum position of the atom in the periodic table and correspondingly what is the atomic number of Z? (ii) Find the number of unpaired electrons in the atom of the element having atomic number 16. (iii) Which of the following ions does not obey Bohr's atomic theory? He^(2+),Li^(2+),B^(3+),Be^(3+) .

What is number of unpaired electrons in V^(3+) ion ?

Name the noble gas and give its atomic number if the number of d-electrons present in this atom is equal to the difference in the no. of electrons present in the p and s-subshells.

Give the number of atoms (""^(12)C) in 12g of carbon.

Number of p electrons in bromine atom are:

The atomic number of cerium (Ce) is 58. the correct electronic configuration of Ce^(3+) ions is-